Liquid fuel burning means and method



Nov. 10, 1931. A. B. FRI-:NIER

LIQUID FUEL BURNING MEANS AND METHOD Filed Aug. 15, 1927 3 Sheets-Sheet l l f' A\\\\\\\\\\\\\\\\\\\\\\\\\* @WM-g? Nov. 10, 1931. A. B. FRENIER LIQUID FUEL BURNING MEANS AND METHOD Filed Aug. 13, 1927 3 Sheets-Sheet 2 huma/4 Nov.10, 1931. A. B. FRENIER LIQUIID FUL BURNING MEANS AND METHOD Filed Aug. 13, 1927 3 Sheets-Sheet 5 Patented Nov. :10,193.1

' tofore filed by UNITED STATES PATENT OFFICE ALBERT B. FRENIER, 0F CHICAGO,

ILLINOIS, ASSIGNOR, BY MESNE ASSIGNMENTS, TO

PETROLEUM HEAT AND POWER.- COMPANY", OF NEW YORK, N. Y., A. CORPORATION OF DELAWARE c LIQUID FUEL BURNING MEANS AND METHOD rIhis invention relates to an. improved method and means of burning liquid fuel in connection with furnaces generally and more especially in connection with steam and hot water, boilers or hot air furnaces used for heating homes or other buildings.

In an application for Letters Patent hereme on the 6th day of August 1925, Serial NumberSAGLl, I described a method and apparatus by which an inert gas (as, for example, the products of combustion taken from the furnace .beyond the burner, as from the stack) was introduced with the atomized or partly atomized fuel or air into the combustion chamber in order to expand the lame,slow down combustion and materially reduce the noise of combustion theretofore had in burners of the kind. In that application was described a method and means for automatically controlling the in- 'troduction of the diluent, namely, the inert products of combustion, so that when applied to the familiar thermostatically controlled intermittently operating burner of domestic use, air alone was introduced in the beginning at the time of ignition into the burner with the atomized liquid fuel and the burner was supplied with fresh air alone until the burner had been brought to full ignition, whereupon 'a predetermined proportion of the diluent gas, namely, the products of combustion, was introduced with the air, which itself Was at the same time reduced in volume. f t

Owing to the diversity of draft-condltions resulting from variation in direction and velocity of Wind, the moisture in the air, and all otherelements under which burners ofthe kind operate, which conditions vary widely not only by day for the same installation, difficulty f was had in-adjustirig the air supply and the supply of d iluent so as to have an ample supply of fresh air from the outsideat the time of ignition and preliminary combustion and a proper proportion of airv after the burner is urning normally with the mixture of air and diluent, to maintain the flame, `Without its being easily subject to abnormal dilation, dampening or blanketingunder the aforesaid varymg draft conditions. i f

for diiferent installations but day Appi-icauon sied August '13, 1927. serial 110.212,781.

In order to lsecure a maximum of eiiiciency from a burner, it must be set for a predetermined capacity of oil consumption,-that is for a predeterminednumber of ounces of oil consumption per minute when a mixture of air and inert gas is fed. When the air and inert gas supply controls are adjusted to burn this predetermined amount of oil with the mixture of air and inert gas, an-excess amount of oil will be supplied when all fresh air is being used With that adjustment, as dur-l ing the ignition stage and When bringing' the burner up to complete combustion. There- `fore it is necessary to introduce more fresh air into tlie'furnace to accomplish complete combustionduring the period of supplying this excess of oil, that is during the period' of ignition and of bringing t-he burner up to complete combustion.

The object of the present invention is to provide a means and method by 'and in which outside fresh air in addition to the air supplied as heretofore through the mixingvalve` which controls'the introduction ofthe product-sncf combustion is suppliedto the burner at thel time of ignition and throughout the preliminary stage of bringing the burner to complete combustion, so as to insure an ample air supply for instant and complete combustion of the aforesaid excess of oil, supplied during said stage Without reference to any adjustment to be subsequently maintained' to producethe proper proportion of air and diluent gas during the period of normal combustion.

This andy other objects and advantages of the invention will appear more fully as I proceed with my specification. l

In the drawings 4 i Figure 1 is a view represen ing a sectional side elevation of a burner installation of the kind described, with Within the lire box, yand means for supplying liquid fuel mixed with air into the said com- 9 bustion chamber, together with the products of combustion such as described in my above named application, with the improvements of the present 4application added. 'p

yFigure 2 isa-transverse section through a combustion chamber Figure 1 in a plane indicated by the line 2 2 of 1igure 1.

Figure 3 is a view representing a vertical section through Figure 4 in a plane indicated by the line 3 3 of Figure 4.

Figure 4 is a view representing a section through Figure 3 in a plane indicated by the line 4 4 of Figure 3.

' Figure 5 is a view representing a. section through Figure 6 in a plane indicated bythe line 5 5 of Figure 6.

Figure 6 is a view representing avsection through Figure 5 in a plane indicated by the line 6 6 Figure 5.

Figures 3 to 6 inclusive are all on a some- -what larger scale than the view shown in Figures 1 and 2.

indicates a furnace of any Figure 7 is a view representing on an enlarged scale a detail section of the aspirator used in connection with the burner in a'plane indicated by the line 7 7 of Figure 2.

Referring now to thatembodiment ofmy invention illustrated in the drawings 10 usual construction provided with a fire box 11. `12 indicates a combustion chamber, which-in this case is a heavy metal box-like structure adapted to confine the fiame. 13 indicates an electric motor-driven fan or blower by means of which air is normally discharged through a pipe 14 into the combustion chamber, said air acting. in the example illustrated, to aspirate and atomize the liquid hydrocarbon fuel supplied by ay pipe 15 from any convenient source of supply. 16 indicates an electric motor controlled by thermostat or other auxiliary automatic control ada ted to close or open the switch in the circuit of the fanmotor and'to actuate the ignition device, as by opening and closing a valve supplying a pilot flame in the combustion chamber. 17 indicates a pipe or conduit leading from a point in the stack 17 A and adapted to introduce the products of combustion into the fan casing whence it is discharged with the fresh air through the pipe 14. Said pipe 17 is connected to the inlet port of a mixing valve casing 18 which opens by passageway 19 into the casing of the blower or fan 13.

20 indicates a mixing valve which deter-- mines the proportion of air and diluent gas to be introduced into the fan casing. ee Figures 5 and 6.)

The mixing valve 20 (as shown ofthe usual form of a damper) is mounted on a spindle 21, which has bearing in and` projects above and below, respectively, the top and bottom walls of the casing 18. At thentop end of the said spindle is fixed a pointer 22 co-related with an arcuate scale 23 to aid in determining the proportionate mixture of air and products of combusion to be obtained. A crank-arm 24 is mounted on the top end of the spindle 21, said crank-arm being fixed to the spindle by means of a set screw for'pro- -Vthe limits of the furnace.

i bell-crank 25, the operation of which is determined by a push-rod 26, the movement of which is determined by the electric motor 16.

The operation of the parts thus far described is substantially the same as in the apparatus of the application hereinbefore referred to, air alone being introduced with the fuel until the necessary time interval has elapsed to bring the burn-er to full combustion. Said time interval may be determined by the operation of the electric motor 16, after which the damper or valve 20 is shifted from the position shown in full lines in Figure 6, 'wherein nothing but air is admitted to the blower, to the dotted line position ing in this position until the combustion is stopped by the operation of the thermostatieor other control.

I now pass to a description fof the novel features intended to be embraced in this application.

27 indicates an lelongated casing which is mounted upon and surrounds the pipe 14 in the neighborhood of the burner 12 and which extends for some distance outwardly beyond Said casing, as shown and in simplest form, consists of an elongated rectangular shell closed at its sides, bottom and end outside of the furnace, but open at the sides and bottom near the burner as indicated at 28. 29 indicates the rear end wall of said shell and 3Q indicates its front end. 31 indicates 4the Vertical side walls of the casing 27, and 32 indicates the bottom wall;

crank-arm 36 which is connected by a link 37 to a crank-arm 38 attached to the bottom end of the spindle 21 of the mixing damper 20. The crank-arm 38 is fixed on the spindle 21 by a set screw 39 so as to be capable of adjustment on the spindle.

'The parts are so arranged and constructed that in the beginning, at the time of ignition f the burner, when the damper 20 is in the position shown in full lines` in Figure 6 e11- tirelycutting off all of the products of combustion, the valve 34 at the rear end ofthe casing 27 is in its fully openposition as shown bythe horizontally disposed dotted lines in Figure 3. There is thus provided a free flow i of ou-tside air to the space about and above theburner 12, by vvay of the valve opening 33, the casing 27, and the opening 28 at the sides and bottom of said casing at its inner end. Thus in the beginning and at the time `of ignition, the burner has not only all the air that entersr through the casing 18 and through the pipe 14 to support combustion of capacity.

Afterfthe burner has been brought to ignition, the operation of the motor 16 and of the push rod 26 actuated thereby permits the spring controlled bell crank arm to swing the valve or damper 20 into the position shown in dotted lines in Figure 6, in order to supply the intended proportionate mixture of products of combustion and of air.` ln this movement of the valve 20 the rotation of its spindle 21, (through the crank arm 38, connecting rod 37, and crank arm 36) acts to close the valve 34 at the rear end of the casing 27. rlhis shuts olf the supply of outside air at this point so that the burner thereafter fburns with the normal intended mixture of air and products of combustion unaffected by any other air supply.

To provide for excess requirements for air i 4 valve 34 is immediately opened When comin the beginning that may be had at some locations, it is preferred to provide in the bottom Wall 32 of the casing 27 an opening 40 which is normally closed by a hand valve A41.

This will make it possible to adjust all parts finally, including the mixing valve 20, its operating parts, and its connections With the valve 34, at the plant before shipment to the place of installation, any unforeseen necessity for air being accommodated by the valve 4l.

The normal operation of the burner is With a predetermined proportion of air and of the inert gas (products of combustion- Warm or hot). lt is for this mixture that the valve 20 is set to occupy the dotted position of Figure 6. lt is with this adjustment that the oil to produce lthe required oil consumption for the designed heat re uirements expanded by reason of the heated inert gals demanded by the burner, is fed y aspiration) with the mixture of air and inert gas,

introduced from the stack or other source of products of combustion.

When oil is fed'`l by an aspirator, the amount of oil drawn in orfed is in direct proportion to the density of the aspirating fluid, namely, the air or the air mixture supplied by the fan or blower.

The burner apparatus to which the application is addressed, is designed to use a mixture of air and products of combustion when burning normally. It is` designed to burn a predetermined number of ounces of oil per minute during its normal state ofburnmg with said mixture of air and products of combustion. However, ignition cannot `be started with said mixture. Pure air is required. Said air is cold in the beginning, as also generally is theburner. dense. The valve 20 is in the full line position shown in Figure 6.

' Since the cold air is denser,- more oil is drawn into the burner and vaporized than` is drawn in by the more rare (less dense) mixture of air and products of combustion of normal burning.` In fact, more oil than will be completely burned, even though air alone and in greater quantity, is admitted to the blower by the valve 20. Additional air, that supplied by the valve 34, is required to burn this excess of oil during the ignition.

The air is` Another advantage of the construction i( herein-disclosed is the cooling `eli'ect on the spraying device used in burners of the kind when and immediately after the burner has ceased to operate. This spraying device is kept coolduring the operating period owing to the continued flow of air; but When this flow of air is shut dovvn said spraying device, being close to the hot combustion chamber, heats up. 'lhe oil in the spraying device will be vaporized or gassified, and carbonization may result. v

ln the `apparatus vdescribed herein, the

the combustion chamber and the undesirable results above mentioned.

While in describing my invention, ll have referred to `many details ofmechanical construction and arrangement of -parts', itis to be understood that vthe invention is in no Way limited thereto except asmay be pointed l out in the accompanying claims.

l claim as my invention:

l. ln a liquid fuel burning apparatus, in combination with a combustion chamber, nieans including an aspirating device for introducing the liquid fuel for introducing a Haine combustible into said combustion chamber, including an air inlet, a normally closed second inlet, aconduit for leading the inert gas to said second inlet, a control device for opening said second inlet, and means actuatednby said control device for introducing an excess of air tothe flaming com'- `bustible when said second inlet is closed.

`2. ln a. liquid fuel burning apparatus, in

vcombination with a combustion chamber,

dame combustible into said eombustlon 25 A ating device located in said conduit Vadjacent chamber, including an air inlet, a normally closed second inlet, a conduit for leading the inert gas to said second inlet, and a control device for opening said second inlet, a normally open conduit for admitting outside air to the liaming combustible, and means for closing said conduit'J upon the opening of lsaid second inlet.

3. ln a liquid fuelburning apparatus, in combination with a combustion chamber,

Ameans for introducing a iiame combustible into said combustion chamber, including an l air inlet, a` normally closed second'inlet, a conduit for leading the inert gas to said second inlet, and a control device for Open ing said second inlet, a normally open oonduit for admitting outside air to the flaming combustible, and m ans actuated by said control device for closing said conduit upon the opening of said second inletf 4. In a liquid fuel burning apparatus, in combination with a fire box of a. furnace, a combustion chamber located therein, a fan, a conduit connecting said fan with the interior of the combustion chamber, an aspirsaid combustion chamber, an oil supply pipe leading to said aspirating device, a casing surrounding said conduit and opening into said lire box, said casing having an inlet end outside of said re box, a normally open valve for closing said inlet opening, a mixing valve casing connected to said blower, having an air inlet and a products of combustion inlet, a mixing valve in said casing normally closing the products of combustion inlet, and automatic means timed to operate after a predetermined interval renots/of combustion inlet.

y day of August,

quired to establish complete combustion in said combustion chamber for closing sald first named valve and for opening sald prodlfn `testimony that l claim the foregoing as my invention, 1 aix my signature this 6 A. D. 1927. ALBERT B. FRENEER.

manege 

